(function anonymous(name, age, _callback) {
    var _x = this._x;
    var _counter = 3; //计数器
    var _done = function () {
      //表示call方法全部执行结束
      _callback();
    };
  
    var _fn0 = _x[0];
    _fn0(name, age, function () {
      if (--_counter === 0) _done();
    });
  
    var _fn1 = _x[1];
    _fn1(name, age, function () {
      if (--_counter === 0) _done();
    });
  
    var _fn2 = _x[2];
    _fn2(name, age, function () {
      if (--_counter === 0) _done();
    });
  });
  